A far-off solar system seems to be forming from a strange
dust whose makeup is unlike that of our and other solar
systems, astronomers say.

The researchers at
the University of California Los Angeles found evidence for
the formation of young, rocky planets from dust circling a
star some 500 light-years away. A light-year is the distance
light travels in a year.

Until now, warm dust
found around other stars has been very similar in
composition to asteroidal or cometary material in our Solar
System, said the universitys Carl Melis, who led the
research while a graduate student.

But this
case is different, he said.

Typically, dust
debris around other stars, or our own Sun, is of the
olivine, pyroxene, or silica variety, minerals commonly
found on Earth, he noted. But this material is not one of
these dust types. We have yet to identify what species it
is.

Melis reported the findings last Wednesday
at the annual American Astronomical Society meeting in
Washington, D.C.

The star, known as HD 131488,
appears to be surrounded by warm dust in a region called the
terrestrial planet zone, where temperatures are similar to
those on Earth, Melis said. He added that the dust seems to
harbour rocky, embryonic planets that have recently
collided.

What makes HD 131488 truly unique is
the unidentified dust species released from the colliding
bodies as well as the presence of cold dust far away from
the star, said astronomer Benjamin Zuckerman of the
university, a co-author of the research. These two
characteristics make HD 131488 unlike any other star with
evidence for massive quantities of dust in its terrestrial
planet zone.

The researchers analyzed the warm
inner dust through infrared imaging and spectroscopy using
an instrument called T-ReCS on the Gemini South telescope in
Chile. Spectroscopy is the analysis of the composition of
objects using the spectrum of light they give off.

Artists rendering of what HD 131488
inner planetary system might look like as two large rocky
bodies collide. Inset illustrates the location of HD 131488
dust belts (top) and comparable regions to our own Solar
System (bottom). HD 131488 hot inner dust belt has similar
separations from its host star as the terrestrial planet
zone around our Sun while the stars cool dust belt has
similar separations from its host star as the Kuiper Belt
region in our Solar System. Also shown for our Solar System
are the orbits of Jupiter, Saturn, Uranus, and Neptune.
(Courtesy Gemini Observatory)

Melis and his team argue that the most
plausible explanation for the unusual abundance of warm dust
is a recent collision of two rocky planetary mass bodies.

While the mysterious warm dust lies at a distance
from HD 131488 that is comparable to the Earth-Sun
separation, the team also found cooler dust about 45 times
further out. This outer dusty region is analogous to the
Kuiper Belt in our own Solar System where many minor planets
orbit the Sun just beyond the orbit of Neptune.

The hot dust almost certainly came from a recent
catastrophic collision between two large rocky bodies in HD
131488 inner planetary system, Melis said. But the cooler
dust is probably left over from planet formation that took
place farther away from HD 131488.

HD 131488
lies in the direction of the constellation Centaurus and is
three times heavier and 33 times more luminous than our own
Sun. The star is part of a major, southern-hemisphere star
forming region known as the Upper-Centaurus-Lupus
association whose members are believed to be about 10
million years old. By contrast, the Sun and Earth are about
4.6 billion years old.

- Courtesy:Gemini Observatory
and World Science staff

Distant solar system forming from mysterious dust, scientists say

Posted by :EdMo

A far-off solar system seems to be forming from a strange dust whose makeup is unlike that of
our and other solar systems, astronomers say.

The researchers at the University of
California Los Angeles found evidence for the formation of young, rocky planets from dust circling a
star some 500 light-years away. A light-year is the distance light travels in a year.

Until now, warm dust found around other stars has been very similar in composition to asteroidal or
cometary material in our Solar System, said the universitys Carl Melis, who led the research while a
graduate student.

But this case is different, he said.

Typically, dust
debris around other stars, or our own Sun, is of the olivine, pyroxene, or silica variety, minerals
commonly found on Earth, he noted. But this material is not one of these dust types. We have yet to
identify what species it is.

Melis reported the findings last Wednesday at the annual
American Astronomical Society meeting in Washington, D.C.

The star, known as HD 131488,
appears to be surrounded by warm dust in a region called the terrestrial planet zone, where
temperatures are similar to those on Earth, Melis said. He added that the dust seems to harbour
rocky, embryonic planets that have recently collided.

What makes HD 131488 truly unique
is the unidentified dust species released from the colliding bodies as well as the presence of cold
dust far away from the star, said astronomer Benjamin Zuckerman of the university, a co-author of
the research. These two characteristics make HD 131488 unlike any other star with evidence for
massive quantities of dust in its terrestrial planet zone.

The researchers analyzed the
warm inner dust through infrared imaging and spectroscopy using an instrument called T-ReCS on the
Gemini South telescope in Chile. Spectroscopy is the analysis of the composition of objects using
the spectrum of light they give off.

Artists
rendering of what HD 131488 inner planetary system might look like as two large rocky bodies
collide. Inset illustrates the location of HD 131488 dust belts (top) and comparable regions to our
own Solar System (bottom). HD 131488 hot inner dust belt has similar separations from its host star
as the terrestrial planet zone around our Sun while the stars cool dust belt has similar separations
from its host star as the Kuiper Belt region in our Solar System. Also shown for our Solar System
are the orbits of Jupiter, Saturn, Uranus, and Neptune. (Courtesy Gemini Observatory)

Melis and his team argue that the most plausible explanation for
the unusual abundance of warm dust is a recent collision of two rocky planetary mass bodies.

While the mysterious warm dust lies at a distance from HD 131488 that is comparable to the
Earth-Sun separation, the team also found cooler dust about 45 times further out. This outer dusty
region is analogous to the Kuiper Belt in our own Solar System where many minor planets orbit the
Sun just beyond the orbit of Neptune.

The hot dust almost certainly came from a recent
catastrophic collision between two large rocky bodies in HD 131488 inner planetary system, Melis
said. But the cooler dust is probably left over from planet formation that took place farther away
from HD 131488.

HD 131488 lies in the direction of the constellation Centaurus and is
three times heavier and 33 times more luminous than our own Sun. The star is part of a major,
southern-hemisphere star forming region known as the Upper-Centaurus-Lupus association whose members
are believed to be about 10 million years old. By contrast, the Sun and Earth are about 4.6 billion
years old.